1 /* 2 * Copyright (C) 2016 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.net.wifi.aware; 18 19 import android.content.Context; 20 import android.content.pm.PackageManager; 21 import android.hardware.wifi.V1_0.Constants; 22 23 /** 24 * Provides utilities for the Wifi Aware manager/service. 25 * 26 * @hide 27 */ 28 public class WifiAwareUtils { 29 /** 30 * Per spec: The Service Name is a UTF-8 encoded string from 1 to 255 bytes in length. The 31 * only acceptable single-byte UTF-8 symbols for a Service Name are alphanumeric values (A-Z, 32 * a-z, 0-9), the hyphen ('-'), the underscore ('_') and the period ('.'). All valid multi-byte 33 * UTF-8 characters are acceptable in a Service Name. 34 */ validateServiceName(byte[] serviceNameData)35 public static void validateServiceName(byte[] serviceNameData) throws IllegalArgumentException { 36 if (serviceNameData == null) { 37 throw new IllegalArgumentException("Invalid service name - null"); 38 } 39 40 if (serviceNameData.length < 1 || serviceNameData.length > 255) { 41 throw new IllegalArgumentException("Invalid service name length - must be between " 42 + "1 and 255 bytes (UTF-8 encoding)"); 43 } 44 45 int index = 0; 46 while (index < serviceNameData.length) { 47 byte b = serviceNameData[index]; 48 if ((b & 0x80) == 0x00) { 49 if (!((b >= '0' && b <= '9') || (b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') 50 || b == '-' || b == '.' || b == '_')) { 51 throw new IllegalArgumentException("Invalid service name - illegal characters," 52 + " allowed = (0-9, a-z,A-Z, -, _, .)"); 53 } 54 } 55 ++index; 56 } 57 } 58 59 /** 60 * Validates that the passphrase is a non-null string of the right size (per the HAL min/max 61 * length parameters). 62 * 63 * @param passphrase Passphrase to test 64 * @return true if passphrase is valid, false if not 65 */ validatePassphrase(String passphrase)66 public static boolean validatePassphrase(String passphrase) { 67 if (passphrase == null 68 || passphrase.length() < Constants.NanParamSizeLimits.MIN_PASSPHRASE_LENGTH 69 || passphrase.length() > Constants.NanParamSizeLimits.MAX_PASSPHRASE_LENGTH) { 70 return false; 71 } 72 73 return true; 74 } 75 76 /** 77 * Validates that the PMK is a non-null byte array of the right size (32 bytes per spec). 78 * 79 * @param pmk PMK to test 80 * @return true if PMK is valid, false if not 81 */ validatePmk(byte[] pmk)82 public static boolean validatePmk(byte[] pmk) { 83 if (pmk == null || pmk.length != 32) { 84 return false; 85 } 86 87 return true; 88 } 89 90 /** 91 * Returns true if the App version is older than minVersion. 92 */ isLegacyVersion(Context context, int minVersion)93 public static boolean isLegacyVersion(Context context, int minVersion) { 94 try { 95 if (context.getPackageManager().getApplicationInfo(context.getOpPackageName(), 0) 96 .targetSdkVersion < minVersion) { 97 return true; 98 } 99 } catch (PackageManager.NameNotFoundException e) { 100 // In case of exception, assume known app (more strict checking) 101 // Note: This case will never happen since checkPackage is 102 // called to verify valididity before checking App's version. 103 } 104 return false; 105 } 106 } 107